Reamer.



Normzsso. V PATENTED DEC. 15. 1903. J. ROSS.

REAMER.

, APPLIOATION FILED APR. 2. 1903.

H0 MODEL.

l V/ Tl VESSES:

'xQocui; K;

UNITED STATES iatentd I ecember 1 5, 1903.

PATENT OFFICE.

JOSEPH ROSS, OF VINCENNES, INDIANA, ASSIGNOR OF ONE-HALF TO ALICE J. BENNETT, OF VINCENNES, INDIANA.

REAMER.

SPECIFICATION formingpart of Letters Patent No. 747,330, dated December 15, 1903.

Application filed April 2, 1903. Serial No. 150,729. (No model.) I

T0 at whom it may concern:

Be it known that I, JOSEPH ROSS, a citizen of the United States,residing at Vincennes,in the county of Knox and State ofIndiana,have invented certain new and useful Improvements in Reamers; and I do declare the following to be a full,clear, and exact'description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same,reference being had to the accompanying drawings,and to the figures of reference marked thereon, which form a part of this specification.

My invention relates to rock and coal drilling, but more particularly to reamers, and has for its object to provide a device for the purpose of reaming out at the bottom a hole that has previously been drilled in rock or coal in order to place a charge of explosive therein, so that the force of said explosive will be in a measure bottled up, thereby increasing the eifectiveness of the same.

'With this object in view my invention consists in the improved reamer, and particu larly in the form and shape of the knives.

Referring to the accompanying drawings, Figure 1 is a perspective view of my reamer, showing knives unfolded. Fig. 2 is a vertical section through the same, and Fig. 3 is a detail perspective of one of the knives. Fig. 4 is a vertical sectional view, showing knives in a folded position. I

Referring to the accompanyingdrawings by reference-numerals, 1 is the shoe or casing, which is provided with a longitudinal slot 2 therein, and 3 is a preferably square vertical opening in the top of said casing, which opening enters said slot 2. The bottom of said casing is rounded, as shown, and the knives 4 are pivoted at 5 within said slot 2 in such a manner that when said knives are folded they are completely within the casing. The knives 4 are provided with rounded ends 6, and the inner edge 7 tapers from the top outwardly,so that the general appearance of the knife is one which is broadest at its outer end. It will be noticed, however, that the pivotal point of said knife is considerably farther in than the inner edge 7, or, in other words, that the knives are substantially L-shaped and have their pivotal points the top of the knives.

on a point along the foot of the L. It is in this construction that my invention principally lies, as will be fully set forth.

8 indicates a washer or guide which is slidably secured on the rod 9 and which is provided with a set-screw 10 or other means for securing said guide at any desired point. At the bottom of said rod, which is preferably square, I provide a head 11, having the two inclined edges 12,which bear against the knives, as shown in Fig. 2.-

Having thus set forth the several parts of my invention, its operation is as follows: The hole having been drilled in the rock or coal by any approved means, the bit and rod are withdrawn and my reamer inserted in the hole and the rod 9 connected to the drill in any approved manner. sorted in the hole so that the bottom of the casing rests at the bottom of the hole. The guide 8 is then pushed just below the edge of the hole, and the rod 9 may be withdrawn a sufficient distance to allow the set-screw 10 or other setting means to be manipulated, so as to hold said guide at the desired point, the purpose of which is to prevent the rod when being revolved from buckling or working about in the hole. The drill having been started, the rod commences to revolve, as does also the reamer, and the head ll is slowly forced between the knives and gradually separates the same, thereby causing said knives to cut into the rock and ream sub stantially a cone-shaped'chamber at the bottom of the hole.

To pass now to the specificoperation and advantages of my reamer. As previously described, the inner edges of my knives incline away from the pivotal points of the knives, and the knives are pivoted at a point considerably within the inner edges thereof. The result of this construction is that when the knives are folded there is considerable space between the lower portion of the inner edges thereof, which space diminishes toward When the head 11 therefore engages the upper ends of the knives to spread the same and passes down between the inner edges of the knives, the opening between said edges becoming wider toward the bottom the head 11 is therefore The reamer is inallowed to descend, acting gradually less upon the inner edges of the knives. The movement of the knives at the point along the inner edges engaged by the head 11 produces a greater movement at the points or ends of the knives, so that while the portion of the knives engaged by the head 11 is given a grad ually-decreased movement as the head 11 descends the point or ends of the knives is given a uniform movement, as a slight movement imparted to the knives at a point near the pivots thereof would produce as great movement at the points or ends of the knives as a greater movement would produce if applied at the center of the knives. Were it not for this construction, which seems very simple, indeed, the head 11 of the rod pressing on the inner edges of the knives would separate the same in any but a uniform manner. In other words, the closer the head 11 of the rod approached the pivot of the knives the greater would be the spread of the knives, so that while the head of the rod would be pressed down uniformly the knives would open faster as the head 11 of the rod approached the pivot 0f the knives, which would cause them to hear an undue strain, making them liable to be twisted or broken. The inclined back of my knives compensates for the tendency of the knives to open faster as the head 11 approaches the pivot, which is of course apparent, as the mechanical principle involved being that of a lever fulcrumed at one end with the power between the fulcrum and the resistance the closer the power to the fulcrum the greater the movement of the other end of the lever for a given moment at the point where the power is applied. It will be seen,therefore, that as the head 11 approaches the pivot of the knives the points engaged by the head 11 are farther apart, which construction causes the knives to be spread uniformly, thereby equalizing the strain thereon during the entire time they are in operation. The knives having rounded tops, as before described, it is only necessary to grasp the top of the rod and draw the same up when it is desired to remove the reamer out of the hole. The head 11 will engage the solid portion above the slot for the knives, and as the reamer is pulled out the rounded ends of the knives engage the wall of the reamed hole, and said knives are folded into the casing, so that the reamer comes out folded, just as it went in.

Having thus set forth my invention, I do not wish to be understood as limiting myself to the exact construction herein set forth, as various slight changes may be made therein which would fall within the limit and scope of my invention, and I consider myself clearly entitled to allsuch changes and modifications.

I claim- 1. In a reamer, the combination of a casing and knives pivoted therein, said knives being substantially L-shaped and pivoted at a point along the foot of the L, the inner edges of said knives being curved so that when said knives are folded within said casing, the opening between the said inner edges of said knives gradually widens toward the pivoted ends of said knives, means adapted to be forced between the said inner edges of said knives, said means engaging the said curved inner edges so that as said means nears the pivotal point of said knives and within the gradually widening space between said knives, said means acts gradually less upon said knives thereby spreading the same uniformly.

2. In a reamer, the combination of a casing and knives pivoted therein, said knives having their inner edges curved so that when the knives are folded within said casing the opening between the said inner edges of said knives gradually widens toward the pivoted ends thereof, means adapted to-be forced between the said inner edges of the knives, said means engaging the said curved inner edges, so that as said means nears the pivotal point of said knives and within the graduallywidening space between said knives, said means acts gradually less upon said knives thereby spreading the same uniformly.

In testimony whereof I affix my signature in presence of two witnesses.

JOSEPH ROSS.

Witnesses:

RUFUS BOWLES, RoBT. F. WEEMS. 

